Piston casting machine



Dec. 16, 1952 A. TowNHlLL PIsToN CASTING MACHINE 5 Sheets-Shelet l' Filed Nov. 16, 1949 Dec. 16, 1952 A. TOWNHILL 2,621,380

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PIsToN CASTING MACHINE 5 Sheets-Sheet 4 Filed Nov. 16, 1949 H+- I m f//L Dec 16, 1952 A. TOWNHILL PIsToN CASTING MACHIE Filed Nov. 16, 1949 5 Sheets-Sheet 5 Patented Dec. 16, 1952 UNITED STATES PATENT OFFICE PIsToNcAsTING MACHINE Arthur Townhill, Cleveland, Ohio, `assignor vto Thompson Products, Inc., Cleveland, Ohio, a

corporation of Ohio Application November 16, 1949, Serial N o. 127,535

(Cl. .Z2- 93) 6 Claims. 1

This invention relates to improvements in casting machines and more particularly to an improved machine ior the casting of pistons vfrom aluminum and similar metals and alloys.

An object of my invention is to provide a simplied form of casting machine having a sectional coreand having a novel form of means for freeing the core sections from the casting-in a simplerA and expeditious manner with no manual effort.

Another object of my invention is to provide av newand improved casting machine for pistons including a sectional core within the inner margins of the mold for the piston and consisting of..

two outer core sections and a central core section spacing the outer core sections apart, and having a novel form and arrangement of operating means therefor arranged to automatically breakthe outerr core sections from the cast piston by power.

A further object of my invention is to provide a piston casting machine having a sectional core withinv the margins of the mold for the piston formed of two outer core sections and a centrall core section withdrawable from the space between the outer core sections after completion of the casting operation, together with means opera-- tively connected with the central core section and engaging the operating means for the outer core sections, for automatically breaking the outer core sections from the cast piston u'pon completion of the withdrawal of the central core sectionv therefrom.

A 'further object of my invention is to provide.

a piston casting machine including two outer core sections and a central core sectionvertically moV- ableinto the space between the outer corelse'c-` tions, to complete the core and hold said core sections in spaced apart relation during the casting operation and to provide operating and control' means for the outer core sections engagedby the means for operating the central core section and held thereby in a slightly contracted position fior my invention showing' the mold in a closed posithe insertion of an expansion control band:

thereon to be cast integrally with the piston, until f movement of the central -core section toward the outer core sections to complete the core, and-'alsol breaking the outer core sections from the pistonl upon complete withdrawal of said central core' section from said outer core sections. A

These and other objects of my invention will appear from time to time as the lfollowing: specification proceeds and with reference to the accom-f panying drawings wherein; -On the drawings:

Figure 1 is a view in side elevation of a .pistonsA casting machine constructed in accordance with:

tion

the mold and core in horizontal section in a closed position;

Figure 5'is a fragmentary plan view somewhat similar toFgure 4- but showing the mold in an open position and the core in a contracted position, to enable the piston to be removed therefrom;`

Figure 6 is a transverse sectional view taken through the mold and core of the machine shown in Figure l vand showing the core in an expanded position; s

vFigure 7 is a View somewhat similar to Figuregl butshowing the central section of the core withdrawn from the mold and showing the outer sec-5 tions of the core broken from the piston;

Figure 8 isa detail planlview of the,seciztional',y mold showing an expansion controlling ring supported thereon .with certain parts of the ring broken away. in order to show the support therefor;

Figure 9 isa fragmentary sectional view taken certain details -of substantially along lines IX-IX of Figure 8; and*l Figure 10 is a fragmentary sectional view somet what similar to Figure 9 but showing the core in a `slightly contracted .position and showing the.- expansion control ring initially placed thereon,` prior to completion of the core by movement of. space between the central core section into the the outer core sections.

' As shown on the drawings The casting machine is mounted between a pair of upright standards llll0 on a yoke-likestruc-- ture Il, disposed therebetween and suitably sup-l ported thereon, and extending upwardly' and' downwardly therefrom. The yoke-like structure..

Il terminates at its upper end into an annular;

flanged.. plate l2 having a frame structure I3 supported thereon and extending therefrom in oppoand having a mold supporting. table ld 4extending along its upper side and form-` site directions,

ing a support for two translationally movable moldsections 15T-I5;

Each-mold ysection vI5 has a substantially rec-v.

Figure 2 is a' fragmentary longitudinal sectional tangular base portion i6 guided at its outer edges in inwardly recessed inclined guides IT-I'I, formed integrally with the table I4 and forming a dove-tail retaining guide for each mold section (see Figure 6) Each mold section l5 also has a segmental portion I8 projecting upwardly from the `oase portion I6, and formed in the form of half of a segment of a cylinder, the inner walls of which form an inner wall of the mold, when the two mold sections I-l5 are in abutting relation with respect to each other. The bottom of each segmental mold portion i8 is herein shown as being recessed to receive .a plate i9 mounted on the top of the table i4 and having a central apertured portion conforming to the inside diameter of the piston skirt and forming the bottom of the mold when the mold sections -15 are moved into abutting relation with respect to each other.

lEach segmental mold portion i8 also has a core pin 2l mounted therein and extending inwardly from .the .inner wall thereof, and coming into engagement with an outer core section 23 of a sectional .core .24 upon closing of the mold. The core .pin .2l forms a core for one of the wrist pin bosses, the boss of which is formed by an inwardly recessed portion 4'2.5 of the outer .core section .23.

A double acting cylinder ZThaving a 4piston (not shown) therein, is mounted .on each end of the table i4, on .an upright .bracket 29, and projects outwardly therefrom. VA piston rod 35 is extensible from each cylinder .and is herein shown as being threaded in a boss 3l projecting upwardly from the base portion i5 .of the mold portion I4, and shown .as being locked thereto by a nut 33o, threaded on said piston rod.

The admission and release of fluid under pressure to and from the opposite ends of the cylinders `ill-2l may be .controlled by suitable valve means which are `not herein shown or .described since'they form no part of my .present invention.

A pouring gate 32 for the mold is shown as being vformed from two semi-circular closure lmembers 33.--33 secured'to the top of the segmental portions 180i the `mold and extending .downwardly along the innerj walls thereof for a short distance. Each of `said closure members has a Arecessed .semi-conical inner wallv portion forming a funnel shaped .pouring .gate Vfor 'the metal when the vtwo mold sections and .closure members )are in abutting relation with respecttoeach other.

The sectional core 24 is formed by thetwo .outer core sections 23-23 extending' through registering centralapertured portions of the .table I4 and plate i9 and guided at `their 'lower ends 'in anannular guide plate t3. The sectional core 24 is completed by -a central .core section 35 movable intoV the .space between the outer core sections 23-23 :and holdingsaid core sections in spaced apart relation with respect to each other against the margin of the apertured portion-of the plate I9. The .central core section 36, as herein shown, has .a substantially T-shaped lower end portion 31 threaded yon the upper end of `a piston rod 39. The piston rod 39 is extensible from a double acting cylinder 40, suitably secured to and .depending from `.the bottom of the yoke-.like structure ,II between .the standards lll-I0. The cylinder 4u and piston rood 39 are adapted to move the central core section 36 Yinto the spacebetween the .outer core sections `2.3-23, to .complete the core, -upon the admission of `duid under pressure to the head end of said cylinder, and'towithdraw the central core sections 23-23 into 4the position shown in Figures 2 and '7 upon the admission of iluid under pressure to the piston rod end thereof.

Each outer core section 23 depends beneath the table it a, substantial distance and has an outwardly extending boss 4i slidably guided in the guide plate 43. Said guide plate is supported on the top of the hanged plate i2 of the yoke structure H and has the table i4 resting thereon. A core draw bar 44 is threaded at its inner end in the boss 4l and is slidably guided in and extends outwardly from the guide plate t3. The core draw bar 44 also extends outwardly through `a dependingvouter side of the frame structure i3 and through the bracket 23, and is slidably guided therein. A compression spring 45 encircles the cuter end of said core draw bar and is interposed between the outside of the bracket 29 and a nut and washer 45 threaded on the outer end of said core draw bar. The springs 45 thus urge and yieldably hold the outer core sections 23--23 in an extreme extended position with respect to the ranold, to denne the internal cavity of the piston Each core draw bar 44 has a lever arm 4'! extending through a slotted portion 49 thereof. Each lever arm 41 is pivoted at its inner end on a pivotal y-pin 5i) suitably supported in the frame structure i3 (see Figure 4). Said lever arms extend laterally from the Vpivotal pins Eil-5i) through the slottedr portions 49-49 of the lever arms 41--41 and beyond the opposite side of frame structure i3 from the pivotal pins 50-50. A clevis 5l is pivoted to each lever arm 41 adjacent the outer margin of the frame structure i3, inwardly of the outer end of said lever arm, so as to leave an end of said lever arm which may be gripped by the operator, if desired.

A separate flexible cable 53 is suitably secured to the clevis 5|. Said cables extend inwardly from said clevises around direction changing pulleys 54-54 journaled on the frame structure I3 on pivotal pins 55-55. From thence the cables 53 extend downwardly to turnbuckles 55-56 and are secured thereto as by threaded rods 5'1-51' secured to the ends of said cables and forming a part of the turnbuckle.

An-eyebolt 59 forms the other adjustable memberof each turnbuckle-SG and depends therefrom. The eye of each'eyebolt 59 is pivotally connected to the outer end of an actuating lever 6i on a pivotal pin 62. The actuating lever 6l is pivoted at its vinner-end to the yoke structure i I adjacent the-outer side thereof on a longitudinally extending pivotal pin 65. An adjustable link 66 formed by a .turnbuck-le 61 having clevises 68-68 extending Afrom opposite ends thereof connects a depending portion 69 of the actuating lever El to a foot pedal 10 pivotally mounted on a rod 'l2 extending across the standards Ill- I0 and secured thereto at its oppositeends. Pressure of the foot on the pedal 10 will Vthus move the outer lcore* sections 23--23 toward each other into the position shown'in Figure 5, .to permit removal of the cast piston 48 therefrom. Upon lrelease of foot pressure from the pedal 10, the springs 45-45 will return the outer-core sections 23-23 `into the partially expanded position shown in Figure 2.

lThe means for initially breakingthe outer core sections 23-23 from the inside of the cast piston, after withdrawal of the central core section 35 therefrom, and for holding ,said core sectionsin a partially contracted position until movement 0f .the central .coresection in a direction to complete the core comprises .a .breaker block 15 engaging the actuating lever 6I. The breaker block is pivotally mounted on the yoke-like structurell on the side thereof opposite the point of pivotal connection of the actuating lever 6| thereto on a transverse pivotal pin '16, mounted at its ends in upright ears ll-J1, extending upwardly from the lower portion of the yoke-like structure I l (see Figure 6). The breaker block 15 has a hollow central portion 'I9 extending around the piston rod 39 and has an engaging end portion 80 adapted to engage a bearing pad 8| extending upwardly from the upper side of the actuating lever 6l. The breaker block 15 is adapted to be engaged by a block 83 mounted on the piston rod 39 immediate the ends thereof and secured thereto. The block 83 is adapted to come into engagement with the breaker block 15 as the center core section is withdrawn from the outer core sections 23-23 and engage said breaker block and depress the actuating lever 6| with a hammer-like jarring action moving said actuating lever from the position shown by solid lines in Figure 6 to the position shown in dotted lines in this figure and by solid lines in Figure 7. This will thus move the outer core sections 23-23 inwardly toward each other to the slightly contracted position shown in Figure 2. The slight contraction of the core sections 23-23 effected by jarring engagemet of the breaker block 75 by the block 13 upon withdrawal of the central core section 36 serves to initially break the outer core sections from the cast piston 48 so as to permit their ready contractionvby foot pressure on the foot pedal 10. The breaker block 15 likewise holds the actuating lever 6I and the outer core sections 23 23 in a slightly contracted position against the compression springs 45-45 to permit an expansion controlling ring 84 to readily be inserted and supported on said outer core sections, and be cast integrally with the piston.

The expansion controlling ring 84 is provided to cause the upper part of the skirt of the piston to contract across its major diameter, as the temperature of the head of the piston rises. The ring 84 thus balances this contraction against the expansion caused by the heat from the head Vof the piston, so that the major diameter of the top of the piston will stay constant in spite of variations in temperature of the head. The skirt of the piston may therefore bear against the cylinder at both sides even when cold, and may expand without binding as has been shown and described in Patent No. 2,262,132 which issued on November 11, 1941, to Otto Carter Berry.

The expansion controlling ring 84 is shown in Figures 8, 9 and 10 as being supported on the sectional core 24 on spaced ears 855-85 extending outwardly from the outer core sections 23-23, above but adjacent the recessed portion 25 forming the bosses for the wrist pin. As herein shown, a rib 86 connects each pair of ears 85-85 tcgether to form a narrow shelf-like support between the ears 85-85 and also to form a recess in the inner wall of the piston just above the wrist pin bosses thereof, and opening to the expansion controlling ring 84. The purpose of this is to permit ready withdrawal or breaking of the outer core sections 23-23 from the cast piston without disturbing the expansion controlling ring 84.

In operation of the machine considering the mold sections l 4*! 4 to be in an open position and the central core section to be withdrawn from the space between the outer core sections 23 23, in this position the block 83 will Vbe in engagement with the breaker block 15 and will hold the actuating lever 6| and flexible cablesV be admitted to the head `ends of the cylinders 21-21 to move the mold sections I 4-l4 to` a closed position. 'At the same time uid under pressure may be admitted to the head end of the cylinder 40, to move the central core section 36 upwardly. As the block 83 moves away from the breaker block 'l5 the springs 45-45 will urge the central core sections 23-23 outwardly and separate the outer core sections 23-23-a distancel sufiicient to permit the central core section 36 to move upwardly therebetween and positively engage the outer core sections 23-23 with the apertured portion of the plate 'I9 to complete the coreand mold and also to tighten the expansion control band 34 on the core.

The mold may then be poured through the pouring gate, the mold thenstaying closedy until the casting is chilled. The time for chilling may be controlled by a suitable timer and valve (not shown) in the circuit supplying fluid under pressure to the cylinders 21-21 and 40. This circuit is 'not shown herein since it forms no part of my present invention. f f

When the casting is chilled, fluid under pressure may be admitted to the piston rod ends of the cylinders 2?' 21 to separate the mold sections |4-I4 and open the mold. At the same time, it may be admitted to the piston rod end of the cylinder 40 to withdraw the central core section from between the outer core sections 23-23. As-the central core section is completely withdrawn, the block 83 will engage the breaker block 'i5 with a jarring action and bring said breaker block into depressing engagement with the actuating lever 6|, and move the end sections 23-23 of the core inwardly a distance sumcient to break them from the inside of the casting. The operator may then put his foot on the foot pedal 'l0 and exert pressure thereon to bring the two parts 'of the core together to the `posi-V tion shown in Figure 5. The piston 48 may then readily be removed from the machine. As the foot of the operator is removed from thefoot pedal 70, the outer core sections 23-23 will'return to the slightly contracted position shown in Figure 2, said outer sections being held in this position by engagement of the block 83 with the breaker block 15. v

Another expansion controlling band 84 may thenbe placed in position on said outer core sections to start the next operating cycle.

It will be lunderstood that modifications and Variations may be eifected without departing from the scope of the novel concepts of the present invention.

I claim as my invention:

1. In a piston casting machine, a sectional core including two outer core sections and a central core section vertically movable into position between said outer core sections, yieldable means urging said outer core sections to move away from each other, means for moving said outer core sections against said yieldable means tcward each other upon withdrawal of said central core section including an actuating 'lever and operative connections between said lever and said outer core sections including separate pivoted levers connected with said core sections and operated by said actuating lever, -a cylinder vhaving a piston rod extensible therefrom and having said central core section mounted thereon to move said central core section into the space vbe'- tween and withdrawing it from said outer core sections, a pivoted breaker block having a free endportion supportedly engaging said lever arm, an abutment member on said piston rod engageable with said breaker block upon complete withdrawal of said central core section from vsaid outer core sections, and moving Said rbreaker block and actuating lever with a jarring action a distance sunicient to break said outer vcore sections from the cast piston and cooperating with said actuating lever and outer core sections to hold said outer core sections against said yieldable means from completely expanding until movement of said central core section toward said outer core sections.

`2. A casting machine comprising a frame, a sectional contractible core mounted on said frame and including two horizontally movable outer core sections and a central core section vertically ymovable in position between said outer core sections to complete the core, yieldable means connected with each outer core section and urging said outer core sections to move away from-each other, a pivoted operating lever, means connecting said lever with said outer core sections to move said outer core sections against said yieldable means upon operation of said lever, a, power operated member having said central core section mounted thereon and movable axially with respect to said outer core sections to move said central core section between and withdraw it from said outer core sections, an engaging block on said axially movable member, a breaker block pivoted on said frame and supported at its free end on said operating lever, said breaker block being disposed beneath and in alignment with said engaging block and being engaged thereby upon withdrawal of said central core section from said outer core sections, and striking said breaker block to depress said operating lever by power for a portion of its stroke length and holding said lever in such a position until said axially movable member moves toward said outer core section.

3. In a casting machine, a support frame, a sectional core including two outer core sections slidably mounted on said frame for rectilinear movement toward and from each other, a central core section vertically movable into the space between said outer core sections, to complete the core, a power operated vertically movable member connected with said central core section to move said central core section into the space between and to withdraw it from said outer core sections, the improvements comprising an actuating lever pivoted on said frame-beneath said outer core sections, means operatively connecting said actuating lever with said outer core sections to move said outer core sections toward each other upon depression of said lever, and an engaging connection between said vertically movable member and said actuating lever', for depressing said actuating lever a limited amount with a jarring action upon withdrawal of said central core section lfrom said Vouter core sections including an abutment member on-said'vertically movable member and a breaker blook pivotally mounted on said frame 'and engaging fsaid iactuatin'g lever, said breaker block beingengaged by saidabutment member to initially break fsaid outer core sections from the Acasting and hold said outer coresections 'from complete expansion bythe 'action of said yieldable means until movement of `said central core section in a direction to'completetheoorestructure.

4. In a-casting'machine including a frame, two outer core `sections slidably mounted 'on Vsaid frame, an inner :core Vsection movable between said outer core sections to hold said outer core sections infseparated expanded relation, a cylinderdisposed beneath said outer core sections, a pistonrod extensible therefrom and having said inner core section ymounted thereon, van axially movable rod connected with each of 'said outr core-sections, springs means connecting with's'aid rods 'and 'biasing sai'd rods and outer core sections into an expanded condition, lever 'means pivotally mounted on said frame and having en'- gageme'n't with said rods for 'moving' said -co're sections into a retracted condition against -said spring means, an operating lever pivoted on said frame beneath said rlever means, means connecting said operating lever withsaid lever means 'to move said core sections against said spring 'means toward each other upon depression of said operating lever, means actuated upon fr'novement of said inner core section out of the space between said outer core section for initially breaking said core sections from the casting with a jarring action and holding said core sections in contracted positions including a breaker bar pivoted on said frame Vfor movement about an axis parallel to the axis of movement of said lever and spaced therefrom and having a free end portion resting on said lever at a point spaced from its pivotal axis, and an engaging block 'on said piston lrod engageable with said 'breaker block 'with a jarring action :upon withdrawal of said center core section.

5. A 'casting machine comprising a frame, a sectionalfcontiactiblecore mounted on saidfr-ame comprising two outer core sections rectilneariy guided for movement towardand from each other anda third inner core section movable vertically between the outer core Vsectior'is and maintaining the core in an expanded condition, means yieldably biasing said outer core sections in expanded relation with respect tol-each other, an operating lever pivoted on said 'frame adyacent one side thereof vand operatively connected with said outer core sections to contract the core against the bias of vsaid yieldable means, a power operated vertically movable extensible member on said -fra'rne having said inner core 'section `mounted on the upper end thereof for upward movement between said outer core sections, a breaker block pivoted on said frame beneath 'said core sections on the opposite side of said extensible member Cfrom said lever arm, and extending across and beyond said extensible member into engagement with 'said lever arm, and a block on said piston ro'd engageable with said breaker block with a hammer-like jarring action upon retractible movement lof said extensible member and withdrawal of said "inner core section from said outer core sections, and effecting pivotal movement of said operating lever to initially contract said outer core sections at the end of the retractible stroke of said extensible member, and holding said lever in position to contract said core sections until movement ofsaid'- extensible member to extend the inner core section.

6. A casting machine comprising a frame, a sectional contractible core mounted on said frame and having two rectilinearly guided outer core sections and a vertically movable inner core section movable between said outer core sections, spring means biasing said outer core sections in expanded positions, an operating lever pivoted on said frame adjacent one side thereof for movement about a horizontal axis and having operative connection with said outer core sections to contract the core against the bias of said spring means, a cylinder on said frame having a piston rod extensible therefrom, said piston rod having said inner core section mounted on the end thereof for extension between said outer core sections, a breaker block pivoted on said frame on the opposite side of said piston rod from the axis of connection of said operating lever to said frame, for movement about an axis parallel to the axis of pivotal movement of said operating lever, said breaker block extending across said piston rod and therebeyond and being supported on said operating lever at its free end, and a block on REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PA'IENTS Number Name Date 590,148 Hall Sept. 14, 1897 1,551,193 Flammang et al. Aug. 25, 1925 1,912,606 Watson June 6, 1933 1,952,199 Flammang et al. Mar. 27, 1934 2,286,994 Nocar June 16, 1942 2,287,524 Jackson June 23, 1942 2,527,537 Fahlman et al Oct. 31. 1950 

